Thin Film Transistor (TFT) Liquid Crystal Display (LCD) comprises Poly-Silicon array substrate and amorphous silicon array substrate, and the difference thereof lies in different transistor characteristics. With respect to one grain of the Poly-Silicon, molecules thereof are aligned in an ordered manner along a certain direction, and thus an electron mobility ratio thereof is multiple times of that of amorphous silicon, in which the molecules are in a disordered state. Poly-Silicon products comprise High Temperature Poly-Silicon (HTPS) product and LTPS product.
During the package procedure of an LTPS TFT-LCD, an excimer laser is used as a heat source. The laser, after passing through a refraction system, can generate a laser beam in which the energy distributes in a uniform manner. The laser beam irradiates a glass substrate with amorphous silicon structure, and the glass substrate can be changed into a Poly-Silicon structure after absorbing energy from the excimer laser. The whole procedure is performed at a temperature lower than 600° C., and thus common glass substrates can all be used.
LTPS-LCD has the advantages of high resolution, high response speed, high brightness, high aperture ratio, and the like. In addition, since in the LTPS-LCD, the silicon crystals are aligned in an ordered manner compared with amorphous silicon, the electron mobility ratio thereof can be one hundred times of that of amorphous silicon. A peripheral driving circuit can be manufactured on the glass substrate, and thus the whole system can be integrated. in this manner, the space and a cost of driving Integrated Circuit (IC) can both be saved, a performance of the array substrate can be improved, and a performance of the LCD can be greatly improved.
However, the manufacturing technology of LTPS array substrate is complicated, and a surface thereof can be possibly not flat. As a result, when the LIPS array substrate is integrated with a color filter substrate, spacers thereof would deviate after being pressed, and thus a risk of light leakage would be generate.